Driver alertness monitoring system

ABSTRACT

A system and methodology for determining the alertness of a driver of a motor vehicle including sensing at least one first movement characteristic of at least a first part of a motor vehicle, sensing at least one second movement characteristic of at least a second part of the motor vehicle, employing at least one time relationship between the at least one first movement characteristic and the at least one second movement characteristic in order to sense and to distinguish between driver initiated movements and non-driver initiated movements and determining the alertness of the driver of the motor vehicle based on at least one relationship between the driver initiated movements and the non-driver initiated movements.

FIELD OF THE INVENTION

[0001] The present invention relates to alertness monitoring for driversof motor vehicles.

BACKGROUND OF THE INVENTION

[0002] The following patents are believed to represent the current stateof the art: U.S. Pat. Nos. 3,227,998; 3,631,446; 3,654,599; 3,935,830;3,980,999; 4,007,357; 4,017,843; 4,104,621; 4,450,438; 4,463,347;4,496,938; 4,509,040; 4,518,954; 4,564,833; 4,565,997; 4,581,607;4,586,032; 4,594,583; 4,604,611; 4,611,199; 4,673,913; 4,794,536;4,853,672; 4,984,646; 4,996,657; 5,057,834; 5,097,917; 5,282,135;5,465,079; 5,488,353; 5,548,273; 5,568,127; 5,570,087; 5,570,698;5,585,785; 5,675,313; 5,684,455; 5,684,462; 5,689,241; 5,709,281;5,714,925; 5,717,606; 5,729,619; 5,745,031; 5,765,116; 5,786,765;5,795,306; 5,798,695; 5,805,079; 5,805,720; 5,813,993; 5,815,070;5,821,860; 5,835,008; 5,835,028; 5,847,648; 5,850,193; 5,867,587;5,900,819; 5,917,415; 5,923,263; 5,925,082; 5,939,989; 5,942,979;5,969,616; 5,982,287; 6,023,227; 6,061,610; 6,064,301; 6,067,020;6,087,941; 6,087,943; 6,091,334; 6,097,286; 6,097,295; 6,172,610.

SUMMARY OF THE INVENTION

[0003] The present invention seeks to provide an improved methodologyand system for monitoring the alertness of drivers of motor vehicles.

[0004] There is thus provided in accordance with a preferred embodimentof the present invention a methodology for determining the alertness ofa driver of a motor vehicle including:

[0005] sensing at least one first movement characteristic of at least afirst part of a motor vehicle;

[0006] sensing at least one second movement characteristic of at least asecond part of the motor vehicle;

[0007] employing at least one time relationship between the at least onefirst movement characteristic and the at least one second movementcharacteristic in order to sense and to distinguish between driverinitiated movements and non-driver initiated movements; and

[0008] determining the alertness of the driver of the motor vehiclebased on at least one relationship between the driver initiatedmovements and the non-driver initiated movements.

[0009] There is also provided in accordance with a preferred embodimentof the present invention, a methodology for determining the alertness ofa driver of a motor vehicle including:

[0010] employing at least one time relationship between at least onefirst movement characteristic of at least a first part of a motorvehicle and at least one second movement characteristic of at least asecond part of the motor vehicle in order to sense and to distinguishbetween driver initiated movements and non-driver initiated movements;and

[0011] determining the alertness of the driver of the motor vehiclebased on at least one relationship between the driver initiatedmovements and the non-driver initiated movements.

[0012] There is additionally provided in accordance with a preferredembodiment of the present invention a methodology for determining thealertness of a driver of a motor vehicle including:

[0013] sensing at least one first movement characteristic of at least afirst part of a motor vehicle;

[0014] sensing at least one second movement characteristic of at least asecond part of a motor vehicle; and

[0015] employing the at least one first movement characteristic and theat least one second movement characteristic in order to determine thealertness of the driver of the motor vehicle.

[0016] There is further provided in accordance with a preferredembodiment of the present invention a methodology for determining thealertness of a driver of a motor vehicle including:

[0017] sensing at least one first movement characteristic of at least afirst part of

[0018] a motor vehicle;

[0019] sensing at least one second movement characteristic of at least asecond part of the motor vehicle;

[0020] employing the at least one first movement characteristic and theat least one second movement characteristic in order to sense driverinitiated movements; and

[0021] determining the alertness of the driver of the motor vehiclebased at least partially on the sensed driver initiated movements.

[0022] There is additionally provided in accordance with a preferredembodiment of the present invention a system for determining thealertness of a driver of a motor vehicle including:

[0023] a first sensor sensing at least one first movement characteristicof at least a first part of a motor vehicle;

[0024] a second sensor sensing at least one second movementcharacteristic of at least a second part of the motor vehicle;

[0025] a distinguisher, employing at least one time relationship betweenthe at least one first movement characteristic and the at least onesecond movement characteristic in order to sense and to distinguishbetween driver initiated movements and non-driver initiated movements;and

[0026] an alertness determiner, determining the alertness of the driverof the motor vehicle based on at least one relationship between thedriver initiated movements and the non-driver initiated movements.

[0027] There is further provided in accordance with a preferredembodiment of the present invention a system for determining thealertness of a driver of a motor vehicle including:

[0028] a distinguisher, employing at least one time relationship betweenat least one first movement characteristic of at least a first part of amotor vehicle and at least one second movement characteristic of atleast a second part of the motor vehicle in order to sense and todistinguish between driver initiated movements and non-driver initiatedmovements; and

[0029] an alertness determiner, determining the alertness of the driverof the motor vehicle based on at least one relationship between thedriver initiated movements and the non-driver initiated movements.

[0030] There is still further provided in accordance with a preferredembodiment of the present invention a system for determining thealertness of a driver of a motor vehicle including:

[0031] a first sensor, sensing at least one first movementcharacteristic of at least a first part of a motor vehicle;

[0032] a second sensor, sensing at least one second movementcharacteristic of at least a second part of a motor vehicle; and

[0033] a distinguisher, employing the at least one first movementcharacteristic and the at least one second movement characteristic inorder to determine the alertness of the driver of the motor vehicle.

[0034] There is yet further in accordance with a preferred embodiment ofthe present invention provided a system for determining the alertness ofa driver of a motor vehicle including:

[0035] a first sensor, sensing at least one first movementcharacteristic of at least a first part of a motor vehicle;

[0036] a second sensor, sensing at least one second movementcharacteristic of at least a second part of the motor vehicle;

[0037] a distinguisher, employing the at least one first movementcharacteristic and the at least one second movement characteristic inorder to sense driver initiated movements; and

[0038] an alertness determiner, determining the alertness of the driverof the motor vehicle based at least partially on the sensed driverinitiated movements.

[0039] There is still further provided in accordance with a preferredembodiment of the present invention a methodology for determining thealertness of a driver of a motor vehicle including:

[0040] sensing at least one characteristic of driver initiated movementsof at least one part of a motor vehicle;

[0041] sensing at least one characteristic of non-driver initiatedmovements of at least one part of a motor vehicle; and

[0042] determining the alertness of the driver of the motor vehiclebased on at least one relationship between the driver initiatedmovements and the non-driver initiated movements.

[0043] There is additionally provided in accordance with a preferredembodiment of the present invention a system for determining thealertness of a driver of a motor vehicle including:

[0044] a driver initiated movement sensor, sensing at least onecharacteristic of driver initiated movements of at least one part of amotor vehicle;

[0045] a non-driver initiated movement sensor, sensing at least onecharacteristic of non-driver initiated movements of at least one part ofa motor vehicle; and

[0046] a determiner, determining the alertness of the driver of themotor vehicle based on at least one relationship between the driverinitiated movements and the non-driver initiated movements.

[0047] Preferably, the at least one characteristic of driver initiatedmovements is extent.

[0048] Preferably, the at least one characteristics of non-driverinitiated movements is extent.

[0049] In accordance with a preferred embodiment of the presentinvention, extent of driver initiated movements includes at least oneof:

[0050] the integrated magnitude of the driver initiated movements;

[0051] the RMS average of the magnitude of the driver initiatedmovements;

[0052] the number of peaks of the driver initiated movements per unittime.

[0053] In accordance with a preferred embodiment of the presentinvention, extent of non-driver initiated movements includes at leastone of:

[0054] the integrated magnitude of the non-driver initiated movements;

[0055] the RMS average of the magnitude of the non-driver initiatedmovements;

[0056] the number of peaks of the non-driver initiated movements perunit time.

[0057] Preferably, the sensing at least one characteristic of driverinitiated movements of at least one part of a motor vehicle and thesensing at least one characteristic of non-driver initiated movements ofat least one part of a motor vehicle include sensing at least one firstmovement characteristic and sensing at least one second movementcharacteristic of the motor vehicle.

[0058] Preferably, the at least one first movement characteristicincludes a steering wheel movement characteristic and the at least onesecond movement characteristic includes a road wheel movementcharacteristic.

[0059] In accordance with a preferred embodiment of the presentinvention, the at least one first movement characteristic and the atleast one second movement characteristic include movementcharacteristics of first and second locations along a steering assemblyextending from a steering wheel to at least one road wheel of the motorvehicle.

[0060] Preferably, the at least one first movement characteristicincludes a steering assembly movement characteristic and the at leastone second movement characteristic includes a vehicle body movementcharacteristic.

[0061] In accordance with a preferred embodiment of the presentinvention, the at least one first movement characteristic includes asteering assembly movement characteristic and the at least one secondmovement characteristic includes a vehicle chassis movementcharacteristic.

[0062] Preferably, the first and second locations are locatedrespectively at or upstream of and at or downstream of a power steeringunit forming part of the steering assembly.

[0063] In accordance with a preferred embodiment of the presentinvention, the first location is at a steering wheel forming part of thesteering assembly.

[0064] Preferably, the at least one first movement characteristic isangular displacement of the steering wheel; and

[0065] the at least one second movement characteristic is a steeringangle of at least one road wheel.

[0066] In accordance with a preferred embodiment of the presentinvention, the at least one first movement characteristic isdisplacement; and

[0067] the at least one second movement characteristic is displacement.

[0068] Alternatively, the at least one first movement characteristic isdisplacement; and

[0069] the at least one second movement characteristic is accelerationin at least one direction.

[0070] In a further alternative, the at least one first movementcharacteristic is displacement; and

[0071] the at least one second movement characteristic is accelerationin at least one direction.

[0072] Preferably, determining also employs the speed of the vehicle.

[0073] In accordance with a preferred embodiment of the presentinvention, the driver initiated movement sensor sensing at least onecharacteristic of driver initiated movements of at least one part of amotor vehicle and the non-driver initiated movement sensor sensing atleast one characteristic of non-driver initiated movements of at leastone part of a motor vehicle include a first sensor, sensing at least onefirst movement characteristic and a second sensor sensing at least onesecond movement characteristic of the motor vehicle.

[0074] Preferably, the system also includes a driver alertness alarm,responsive to an alarm from the driver alertness determiner forproviding an alarm to a driver deemed not to be sufficiently alert.

BRIEF DESCRIPTION OF THE DRAWINGS

[0075] The present invention will be understood and appreciated morefully from the following detailed description, taken in conjunction withthe drawings in which:

[0076]FIGS. 1A and 1B are simplified pictorial illustrations of amethodology for determining the alertness of a driver of a motor vehiclein accordance with a preferred embodiment of the present invention,respectively illustrating operation when a driver is alert and when adriver is not alert;

[0077]FIG. 2 is a simplified pictorial illustration of a systemoperative to provide the functionality of FIGS. 1A and 1B and showinginter alia a steering assembly and part of a chassis of a typical motorvehicle as well as illustrating a plurality of locations wheremeasurements of motion may be made in accordance with a preferredembodiment of the present invention;

[0078]FIG. 3A is a simplified flow chart of the functionality of FIGS.1A and 1B in accordance with one preferred embodiment of the presentinvention;

[0079]FIG. 3B is a simplified flow chart of the functionality of FIGS.1A and 1B in accordance with another preferred embodiment of the presentinvention;

[0080]FIG. 3C is a simplified flow chart of the functionality of FIGS.1A and 1B in accordance with yet another preferred embodiment of thepresent invention;

[0081]FIG. 4A is an illustration of the functionality of FIGS. 1A and 1Bin accordance with one preferred embodiment of the present inventionover a first time period corresponding to a first set of drivingconditions and driver conditions;

[0082]FIG. 4B is an illustration of the functionality of FIGS. 1A and 1Bin accordance with one preferred embodiment of the present inventionover a second time period corresponding to a second set of drivingconditions and driver conditions;

[0083]FIG. 4C is an illustration of the functionality of FIGS. 1A and 1Bin accordance with one preferred embodiment of the present inventionover a third time period corresponding to a third set of drivingconditions and driver conditions;

[0084]FIG. 5 is a diagram in the form appearing also in FIGS. 1A and 1B,illustrating data points produced in accordance with the presentinvention from the data appearing in FIGS. 4A, 4B and 4C; and

[0085]FIG. 6 is a simplified flow chart illustrating application ofalertness criteria to driving samples in accordance with a preferredembodiment of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0086] Reference is now made to FIGS. 1A and 1B, which are simplifiedpictorial illustrations of a system and methodology for determining thealertness of a driver of a motor vehicle in accordance with a preferredembodiment of the present invention, respectively illustrating operationwhen a driver is alert and when a driver is not alert.

[0087] As seen in FIGS. 1A and 1B, a determination of the alertness ofthe driver is made based on a statistical relationship between at leastone characteristic of driver initiated movements of at least one part ofa motor vehicle and at least one characteristic of non-driver initiatedmovements of at least one part of a motor vehicle.

[0088] A typical driver initiated movement includes controlled movementsof the motor vehicle, as for example by the driver turning the steeringwheel. A typical non-driver initiated movements of the motor vehicleincludes uncontrolled movements of the motor vehicle, as for example bythe car encountering an uneven section of the road, a gust or unbalancedvehicle wheels.

[0089] In the preferred embodiment of the invention illustrated in FIGS.1A and 1B, the at least one characteristic of both driver initiatedmovements and of non-driver initiated movements is extent. The use ofthe term “extent”, when used with “driver initiated motions” and“non-driver initiated motions”, is intended to convey measures of suchmotions. This measure may be derived in one or more different ways.

[0090] It is appreciated that alternatively different characteristics ormetrics may be employed for driver initiated movements and fornon-driver initiated movements.

[0091] As will be described hereinbelow, for the purposes of the presentinvention, extent may be one or more of at least the followingparameters for driver initiated movements:

[0092] the integrated magnitude of the driver initiated movements;

[0093] the RMS average of the magnitude of the driver initiatedmovements;

[0094] the number of peaks of the driver initiated movements per unittime.

[0095] Likewise, extent may be one or more of at least the followingparameters for non-driver initiated movements:

[0096] the integrated magnitude of the non-driver initiated movements;

[0097] the RMS average of the magnitude of the non-driver initiatedmovements;

[0098] the number of peaks of the non-driver initiated movements perunit time.

[0099] Alternatively or additionally extent may involve one or moreadditional parameters. The term “magnitude” as used in the presentapplication may refer to the amount of movement, irrespective of whetherthat movement is linear movement, angular movement or a combinationthereof. Additionally, the term “magnitude” as used in the presentapplication may also refer to a mathematical combination of the movementand another parameter, such as the vehicle speed.

[0100] The “THRESHOLD” lines shown in FIGS. 1A and 1B define apredetermined relationship between driver initiated movements andnon-driver initiated movements and shows the minimum extent of thedriver initiated movements expected for the corresponding extent ofnon-driver initiated movements, which may be typically measured for aseries of alert drivers or, alternatively may be typically establishedfor specific alert drivers.

[0101] In practice, the threshold is preferably determined bycorrelating a statistically valid sampling of the results of themeasuring the driver alertness, see for example the data presented inFIG. 5, with acceptable levels of driver alertness as measured byexternal means, such as visual records of the appearance of the driveror outputs of various biometric sensors. In setting the threshold,typically care is taken not to provide false alarms unnecessarily, whichwould result in driver dissatisfaction and refusal to use the system. Inpractice, a threshold is determined or selectable, which does not failto provide an alarm when the driver is not sufficiently alert.

[0102] Turning to FIG. 1A, it is appreciated that operation of a motorvehicle by an alert driver is preferably characterized in that for atleast a predetermined majority of a multiplicity of different timeperiods, a metric of the extent of driver initiated movements at leastequals a corresponding metric of the extent of non-driver initiatedmovements.

[0103]FIG. 1B shows that corresponding operation of a motor vehicle byan non-alert driver is preferably characterized in that for at least apredetermined majority of a multiplicity of different time periods, ametric of the extent of driver initiated movements does not at leastequal a corresponding metric of the extent of non-driver initiatedmovements.

[0104] Thus, it may be understood that, for example, when a driver isalert, as the magnitude of non-driver initiated motions increases, thefrequency of occurrence of driver initiated motions should increasegenerally correspondingly.

[0105] Reference is now made to FIG. 2, which is a simplified pictorialillustration of a steering assembly and part of a chassis of a typicalmotor vehicle, illustrating a plurality of locations therealong wheremeasurements of motion may be made in accordance with a preferredembodiment of the present invention.

[0106] In the motor vehicle shown in FIG. 2 and designated generally byreference numeral 100, there is provided a conventional steeringassembly 102, including a steering wheel 104, a steering wheel shaft106, connecting the steering wheel to a power steering unit 108, as wellas right and left linkages 110 and 112 which connect the power steeringunit to road wheels 114 and 116, respectively.

[0107] It is appreciated that the present invention may also be usedwith motor vehicles, which do not include a power steering unit 108.

[0108] In accordance with a preferred embodiment of the presentinvention, a driver alertness determining system is provided including acomputation unit 120 which receives inputs from one or more angularmotion sensors, preferably including a first angular motion sensor 122disposed adjacent steering wheel shaft 106 at the steering wheel sidethereof, a second angular motion sensor 124 disposed adjacent steeringwheel shaft 106 at the power steering unit side thereof, a third angularmotion sensor 126 disposed adjacent one of linkages 110 and 112, afourth angular motion sensor 128 disposed adjacent a road wheel 114 or116 and an acceleration sensor 130 mounted on a chassis portion 132thereof.

[0109] Computation unit 120 also preferably receives an input from avehicle speed sensor 134 and provides a driver sensible output via adriver alertness alarm 136, which may be any suitable alarm such as atactile, visual, audio or audiovisual alarm.

[0110] As will be described hereinafter in detail, preferably inputs arereceived from two of the angular motion sensors, one adjacent the roadwheels and one adjacent the steering wheel. Alternatively oradditionally, an input from the acceleration sensor 130 in combinationwith one or more inputs from angular motion sensors may be employed.

[0111] Reference is now made to FIG. 3A, which is a simplified flowchart illustrating the functionality of FIGS. 1A and 1B in accordancewith one preferred embodiment of the present invention. As seen in FIG.3A, data from a road wheel influenced displacement sensor, such aseither of sensors 126 and 128, is normalized, at block 200, preferablyto eliminate variations in measurements resulting from differences inthe magnitudes of motion sensed by different sensors. Typical normalizeddata from the road wheel sensor 128 (FIG. 2) as a function of time,appear as a solid line in trace A1 of FIG. 4A, trace B1 of FIG. 4B andtrace C1 of FIG. 4C.

[0112] It is appreciated that the term “displacement” as used throughoutmay, where suitable, refers to either or both of linear and angulardisplacements. In the case of steering wheel motion, the senseddisplacement is angular displacement. In the case of road wheeldisplacement, either or both of angular displacement of the road wheelitself and linear displacement of elements coupled thereto may besensed.

[0113] The output of block 200, is then filtered, at block 202, toremove noise, which in this case preferably includes all signalcomponents having frequencies in excess of approximately 10 Hz. Typicalnormalized and filtered data from the road wheel sensor 128 (FIG. 2) asa function of time, appear as a solid line in trace A2 of FIG. 4A, traceB2 of FIG. 4B and trace C2 of FIG. 4C.

[0114] The output of block 202 is split into high and low frequencycomponents, preferably above and below 4 Hz, as indicated in block 204.The high frequency component of typical normalized and filtered datafrom the road wheel sensor 128 (FIG. 2) appears as trace A3 of FIG. 4A,trace B3 of FIG. 4B and trace C3 of FIG. 4C. The low frequency componentof typical normalized and filtered data from sensor 128 (FIG. 2) as afunction of time, appear as a solid line in each of trace A4 of FIG. 4A,trace B4 of FIG. 4B and trace C4 of FIG. 4C.

[0115] It is appreciated that the high frequency component, namely, thecomponent above 4 Hz, is typical of the non-driver initiated movements.However, the component below 4 Hz may include both driver initiatedmovements and non-driver initiated movements.

[0116] The high frequency component output of block 204 is furtherprocessed, together with the data of the vehicle sensor 134 (FIG. 2), asindicated in a block 206, to further characterize this component. Thefunctionality of block 206 may include one or more of calculating RMSvalues, average values, and standard deviations of the high frequencycomponent, typically coupled with the data from the vehicle speed sensor134 (FIG. 2), over successive time periods, three of which arerepresented by respective FIGS. 4A, 4B and 4C.

[0117] The output of block 206 is employed to determine the extent ofnon-driver initiated motion, as indicated in a block 208.

[0118] The low frequency component output of block 204 is furtherprocessed as indicated in a block 210, as is described hereinbelow.

[0119] Data from a steering wheel influenced angular displacementsensor, such as either of sensors 122 and 124, is normalized, at block212, preferably to eliminate variations in measurements resulting fromdifferences in the magnitudes of the motion sensed by different sensors.Typical normalized data from the steering wheel sensor 122 (FIG. 2) as afunction of time, appear as a dashed line in trace A1 of FIG. 4A, traceB1 of FIG. 4B and trace C1 of FIG. 4C.

[0120] The output of block 212, is then filtered, at block 214, toremove noise, which in this case preferably includes all signalcomponents having frequencies in excess of approximately 10 Hz. Typicalnormalized and filtered data from the steering wheel sensor 122 (FIG. 2)as a function of time, appear as a dashed line in trace A2 of FIG. 4A,trace B2 of FIG. 4B and trace C2 of FIG. 4C.

[0121] The output of block 214 is preferably supplied to block 210,which is operative to determine the sign of the phase difference betweenthe output of block 214 and the output of block 204, which arerespectively represented by the dashed and solid lines in trace A4 ofFIG. 4A, trace B4 of FIG. 4B and trace C4 of FIG. 4C for each of amultiplicity of discrete time durations. This phase difference isdefined to be positive, when the output of block 214, representing thesteering wheel influenced motion, leads the output of block 204,representing the low frequency component of the road wheel influencedmotion.

[0122] There exist various known techniques for determining the phasedifference, any suitable one of which may be employed herein. Theparticular technique employed does not form part of the presentinvention.

[0123] When the phase difference is positive the relevant time durationto which that data relates is indicated, at block 216, to be driverinitiated motion duration, indicated by a relatively thick line in traceA5 of FIG. 4A, trace B5 of FIG. 4B and trace C5 of FIG. 4C. The datarepresenting driver initiated motion is then analyzed, at block 218,typically to determine the frequency of occurrence of driver initiatedmotions, which is an indication of the extent of driver initiatedmotions. Alternatively or additionally to determining the frequency ofoccurrence of driver initiated motions, any other suitable metric of theextent of driver initiated motions may be employed.

[0124] The frequency of occurrence of driver initiated motions may bedetermined by counting the number of extrema points in the dashed lineappearing in trace A4 of FIG. 4A, trace B4 of FIG. 4B and trace C4 ofFIG. 4C during the driver initiated motion durations corresponding tothe relatively thick lines in trace A5 of FIG. 4A, trace B5 of FIG. 4Band trace C5 of FIG. 4C. These extrema points are indicated by circlesdrawn on the relatively thick line in trace A5 of FIG. 4A, trace B5 ofFIG. 4B and trace C5 of FIG. 4C.

[0125] When the phase difference is negative, the relevant time durationto which that data relates is indicated, at block 220 to be non-driverinitiated motion duration, indicated by a relatively thin line in traceA5 of FIG. 4A, trace B5 of FIG. 4B and trace C5 of FIG. 4C. The datarepresenting non-driver initiated motion is then analyzed, at block 222,in order to further characterize this data. The functionality of block222 may include one or more of calculating RMS values, average values,and standard deviations of the low frequency component, typicallycoupled with the data of the vehicle speed sensor (FIG. 2), oversuccessive time periods, three of which are represented by respectiveFIGS. 4A, 4B and 4C.

[0126] The output of block 222 is supplied to block 208 along with theoutput from block 206 in order to determine the extent of non-driverinitiated motion. The functionality of block 208 may be summarized asproviding a metric indicating the level of non-driver initiated motionover successive time periods, three of which are represented byrespective FIGS. 4A, 4B and 4C.

[0127] The level of non-driver initiated motion may be expressed in anumber of possible ways, such as a linear or non-linear combination oflow frequency and high frequency data, which reflects one or both ofmagnitude of such motion and frequency of direction change of suchmotion. Preferably, a linear combination of the low frequency and highfrequency data is employed and reflects both magnitude and frequency ofdirection change.

[0128] The outputs of blocks 208 and 218 are employed in a block 224 todetermine whether a driver meets alertness criteria, as will bedescribed hereinbelow with reference to FIGS. 5 and 6.

[0129] Reference is now made to FIG. 3B, which is a simplified flowchart illustrating the functionality of FIGS. 1A and 1B in accordancewith another preferred embodiment of the present invention. Generallyspeaking, the embodiment of FIG. 3B differs from that of FIG. 3A in thatthe embodiment of FIG. 3B does not separate or separately employ thehigh frequency portion of the output of a road wheel displacementsensor.

[0130] As seen in FIG. 3B, data from a road wheel influenceddisplacement sensor, such as either of sensors 126 and 128, isnormalized, at block 300, preferably to eliminate variations inmeasurements resulting from differences in the magnitudes of motionsensed by different sensors. Typical normalized data from the road wheelsensor 128 (FIG. 2) as a function of time, appear as a solid line intrace A1 of FIG. 4A, trace B1 of FIG. 4B and trace C1 of FIG. 4C.

[0131] The output of block 300, is then filtered, at block 302, toremove noise and other irrelevant data, which in this case preferablyincludes all signal components having frequencies in excess ofapproximately 4 Hz. Typical normalized and filtered data from the roadwheel sensor 128 (FIG. 2) as a function of time, appear as a solid linein trace A4 of FIG. 4A, trace B4 of FIG. 4B and trace C4 of FIG. 4C.

[0132] The output of block 302 is further processed as indicated in ablock 310, as is described hereinbelow.

[0133] Data from a steering wheel influenced angular displacementsensor, such as either of sensors 122 and 124, is normalized, at block312, preferably to eliminate variations in measurements resulting fromdifferences in the magnitudes of motion sensed by different sensors.Typical normalized data from the steering wheel sensor 122 (FIG. 2) as afunction of time, appear as a dashed line in trace A1 of FIG. 4A, traceB1 of FIG. 4B and trace C1 of FIG. 4C.

[0134] The output of block 312, is then filtered, at block 314, toremove noise, which in this case preferably includes all signalcomponents having frequencies in excess of approximately 4 Hz. Typicalnormalized and filtered data from sensor the steering wheel 122 (FIG. 2)as a function of time, appear as a dashed line in trace A2 of FIG. 4A,trace B2 of FIG. 4B and trace C2 of FIG. 4C.

[0135] The output of block 314 is preferably supplied to block 310,which is operative to determine the sign of the phase difference betweenthe output of block 314 and the output of block 302, which arerespectively represented by the dashed and solid lines in trace A4 ofFIG. 4A, trace B4 of FIG. 4B and trace C4 of FIG. 4C for each of amultiplicity of discrete time durations. This phase difference isdefined to be positive, when the output of block 314, representing thesteering wheel influenced motion, leads the output of block 302,representing the road wheel influenced motion.

[0136] There exist various known techniques for determining the phasedifference, any suitable one of which may be employed herein. Theparticular technique employed does not form part of the presentinvention.

[0137] When the phase difference is positive, the relevant time durationto which that data relates is indicated, at block 316, to be driverinitiated motion duration, indicated by a relatively thick line in traceA5 of FIG. 4A, trace B5 of FIG. 4B and trace C5 of FIG. 4C. The datarepresenting driver initiated motion is then analyzed, at block 318,typically to determine the frequency of occurrence of driver initiatedmotions, which is an indication of the extent of driver initiatedmotions. Alternatively or additionally to determining the frequency ofoccurrence of driver initiated motions, any other suitable metric of theextent of driver initiated motions may be employed.

[0138] The frequency of occurrence of driver initiated motions may bedetermined by counting the number of extrema points in the dashed lineappearing in trace A4 of FIG. 4A, trace B4 of FIG. 4B and trace C4 ofFIG. 4C during the driver initiated motion durations corresponding tothe relatively thick lines in trace A5 of FIG. 4A, trace B5 of FIG. 4Band trace C5 of FIG. 4C. These extrema points are indicated by circlesdrawn on the relatively thick line in trace A5 of FIG. 4A, trace B5 ofFIG. 4B and trace C5 of FIG. 4C.

[0139] When the phase difference is negative, the relevant time durationto which that data relates is indicated, at block 320 to be non-driverinitiated motion duration, indicated by a relatively thin line in traceA5 of FIG. 4A, trace B5 of FIG. 4B and trace C5 of FIG. 4C. The datarepresenting non-driver initiated motion is then analyzed, at block 322,in order to further characterize this data. The functionality of block322 may include one or more of calculating RMS values, average values,and standard deviations of the low frequency component, typicallycoupled with the data of the vehicle speed sensor 134 (FIG. 2), oversuccessive time periods, three of which are represented by respectiveFIGS. 4A, 4B and 4C.

[0140] The output of block 322 is supplied to block 308 in order todetermine the extent of non-driver initiated motion. The functionalityof block 308 may be summarized as providing a metric indicating thelevel of non-driver initiated motion over successive time periods, threeof which are represented by respective FIGS. 4A, 4B and 4C.

[0141] The level of non-driver initiated motion may be expressed in anumber of possible ways, such as a linear or non-linear combination ofdata, which reflects one or both of magnitude of such motion andfrequency of direction change of such motion. Preferably, a linearcombination of the data is employed and reflects both magnitude andfrequency of direction change.

[0142] The outputs of blocks 308 and 318 are employed in a block 324 todetermine whether a driver meets alertness criteria, as will bedescribed hereinbelow with reference to FIGS. 5 and 6.

[0143] Reference is now made to FIG. 3C, which is a simplified flowchart illustrating the functionality of FIGS. 1A and 1B in accordancewith still another preferred embodiment of the present invention.Generally speaking, the embodiment of FIG. 3C differs from that of FIG.3A in that data from an accelerometer, such as the lateral component ofdata from an acceleration sensor 130 (FIG. 2) fixed to the chassis of avehicle, is employed instead of data from a road wheel influenceddisplacement sensor. It is appreciated that as a further alternative,the data from both a road wheel influenced displacement sensor and froman accelerometer may be employed. It is also appreciated that a verticalcomponent from an accelerometer may be employed to represent non-driverinitiated motion.

[0144] As seen in FIG. 3C, data from an accelerometer, such asacceleration sensor 130, is normalized, at block 400, preferably toeliminate variations in measurements resulting from differences in themagnitudes and dimensions of motions sensed by different sensors.Typically, the normalized data from the lateral component of the outputof acceleration sensor 130 (FIG. 2) as a function of time, appear as asolid line in trace A1 of FIG. 4A, trace B1 of FIG. 4B and trace C1 ofFIG. 4C.

[0145] The output of block 400, is then filtered, at block 402, toremove noise, which in this case preferably includes all signalcomponents having frequencies in excess of approximately 10 Hz. Typicalthe normalized and filtered data from the lateral component of theoutput of acceleration sensor 130 (FIG. 2) as a function of time, appearas a solid line in trace A2 of FIG. 4A, trace B2 of FIG. 4B and trace C2of FIG. 4C.

[0146] The output of block 402 is split into high and low frequencycomponents, preferably above and below 4 Hz, as indicated in block 404.The high frequency component of typical normalized and filtered datafrom the lateral component of the output of acceleration sensor 130(FIG. 2) as a functions of time, appear as trace A3 of FIG. 4A, trace B3of FIG. 4B and trace C3 of FIG. 4C. The low frequency component oftypical normalized and filtered data from the lateral component of theoutput of acceleration sensor 130 (FIG. 2) as a function of time, appearas a solid line in each of trace A4 of FIG. 4A, trace B4 of FIG. 4B andtrace C4 of FIG. 4C.

[0147] The high frequency component output of block 404 is furtherprocessed, typically with the data from the vehicle speed sensor 134(FIG. 2), as indicated in a block 406, to further characterize thiscomponent. The functionality of block 406 may include one or more ofcalculating RMS values, average values, and standard deviations of thehigh frequency component, typically with the data from the vehicle speedsensor 134 (FIG. 2), over successive time periods, three of which arerepresented by respective FIGS. 4A, 4B and 4C. Optionally, a verticalcomponent of the output of acceleration sensor 130 may also be employedin block 406.

[0148] The output of block 406 is employed to determine the extent ofnon-driver initiated motion, as indicated in a block 408.

[0149] The low frequency component output of block 404 is furtherprocessed as indicated in a block 410, as is described hereinbelow.

[0150] Data from a steering wheel influenced angular displacementsensor, such as either of sensors 122 and 124, is normalized, at block412, preferably to eliminate variations in measurements resulting fromdifferences in the magnitudes of motion sensed by different sensors.Typical normalized data from the steering wheel sensor 122 (FIG. 2) as afunction of time, appear as a dashed line in trace Al of FIG. 4A, traceB1 of FIG. 4B and trace C1 of FIG. 4C.

[0151] The output of block 412, is then filtered, at block 414, toremove noise, which in this case preferably includes all signalcomponents having frequencies in excess of approximately 10 Hz. Typicalnormalized and filtered data from the steering wheel sensor 122 (FIG. 2)as a function of time, appear as a dashed line in trace A2 of FIG. 4A,trace B2 of FIG. 4B and trace C2 of FIG. 4C.

[0152] The output of block 414 is preferably supplied to block 410,which is operative to determine the sign of the phase difference betweenthe output of block 414 and the output of block 404, which arerespectively represented by the dashed and solid lines in trace A4 ofFIG. 4A, trace B4 of FIG. 4B and trace C4 of FIG. 4C for each of amultiplicity of discrete time durations. This phase difference isdefined to be positive, when the output of block 414, representing thesteering wheel influenced motion, leads the output of block 404,representing the low frequency component of the road wheel influencedmotion.

[0153] There exist various known techniques for determining the phasedifference, any suitable one of which may be employed herein. Theparticular technique employed does not form part of the presentinvention.

[0154] When the phase difference is positive, the relevant time durationto which that data relates is indicated, at block 416, to be driverinitiated motion duration, indicated by a relatively thick line in traceA5 of FIG. 4A, trace B5 of FIG. 4B and trace C5 of FIG. 4C. The datarepresenting driver initiated motion is then analyzed, at block 418,typically to determine the frequency of occurrence of driver initiatedmotions, which is an indication of the extent of driver initiatedmotions. Alternatively or additionally to determining the frequency ofoccurrence of driver initiated motions, any other suitable metric of theextent of driver initiated motions may be employed.

[0155] The frequency of occurrence of driver initiated motions may bedetermined by counting the number of extrema points in the dashed lineappearing in trace A4 of FIG. 4A, trace B4 of FIG. 4B and trace C4 ofFIG. 4C during the driver initiated motion durations corresponding tothe relatively thick lines in trace A5 of FIG. 4A, trace B5 of FIG. 4Band trace C5 of FIG. 4C. These extrema points are indicated by circlesdrawn on the relatively thick line in trace A5 of FIG. 4A, trace B5 ofFIG. 4B and trace C5 of FIG. 4C.

[0156] When the phase difference is negative, the relevant time durationto which that data relates is indicated, at block 420 to be non-driverinitiated motion duration, indicated by a relatively thin line in traceA5 of FIG. 4A, trace B5 of FIG. 4B and trace C5 of FIG. 4C. The datarepresenting non-driver initiated motion is then analyzed, at block 422,in order to further characterize this data. The functionality of block422 may include one or more of calculating RMS values, average values,and standard deviations of the low frequency component, typically withthe data from the vehicle speed sensor 134 (FIG. 2), over successivetime periods, three of which are represented by respective FIGS. 4A, 4Band 4C.

[0157] The output of block 422 is supplied to block 408 along with theoutput from block 406 in order to determine the extent of non-driverinitiated motion. The functionality of block 408 may be summarized asproviding a metric indicating the level of non-driver initiated motionover successive time periods, three of which are represented byrespective FIGS. 4A, 4B and 4C.

[0158] The level of non-driver initiated motion may be expressed in anumber of possible ways, such as a linear or non-linear combination oflow frequency and high frequency data, which reflects one or both ofmagnitude of such motion and frequency of direction change of suchmotion. Preferably, a linear combination of the low frequency and highfrequency data is employed and reflects both magnitude and frequency ofdirection change.

[0159] The outputs of blocks 408 and 418 are employed in a block 424 todetermine whether a driver meets alertness criteria, as will bedescribed hereinbelow with reference to FIGS. 5 and 6.

[0160] It is appreciated that in the embodiments of FIGS. 3A and 3B, theoutput of acceleration sensor 130 may be employed in place of or inaddition to the output of a road-wheel influenced angular displacementsensor.

[0161] Reference is now made to FIGS. 5 and 6, which illustrateutilization of determinations of extent of driver initiated andnon-driver initiated motions for determining driver alertness.Typically, the Threshold Line is initially determined as discussedhereinabove (step 600, FIG. 6).

[0162] Preferably, as seen in FIG. 5, for each given time period, suchas the three time periods represented by FIGS. 4A, 4B and 4C, the extentof driver initiated motion and the extent of non-driver initiated motionare plotted in “Extent Space” (step 602, FIG. 6). Each such time periodis represented by a single point in “Extent Space”. Thus it may be seenin FIG. 5, that a point 550 represents the extent of driver initiatedmotion and the extent of non-driver initiated motion for the time periodrepresented by FIG. 4A.

[0163] In the embodiments of FIGS. 3A, 3B and 3C, the extent of driverinitiated motions is preferably derived from the frequency of theiroccurrence, as exemplified by the number of circles appearing in tracesA5, B5 and C5, respectively in FIGS. 4A, 4B and 4C.

[0164] In the embodiments of FIGS. 3A and 3C, the extent of non-driverinitiated motions is preferably derived from the amplitude of the highfrequency component of the non-driver initiated motions, as exemplifiedby the amplitudes appearing in traces A3, B3 and C3, typically combinedwith the amplitude of the low frequency component of the non-driverinitiated motions taken together with other data relating thereto, suchas the frequency of occurrence.

[0165] In the embodiment of FIG. 3B, the extent of non-driver initiatedmotions is preferably derived from the amplitude of the low frequencycomponent of the non-driver initiated motions taken together with otherdata relating thereto, such as the frequency of occurrence.

[0166] Referring again to FIG. 5, point 560 represents the extent ofdriver initiated motion and the extent of non-driver initiated motionfor the time period represented by FIG. 4B and pointy 570 represents theextent of driver initiated motion and the extent of non-driver initiatedmotion for the time period represented by FIG. 4C.

[0167] Similar plots in FIGS. 1A and 1B represent the extent of driverinitiated motion and the extent of non-driver initiated motion for arelatively large number of time periods.

[0168] As seen in FIGS. 1A, 1B and 5, there appears a threshold linethat differentiates couples of the extent of driver initiated motion andthe extent of non-driver initiated motion for a given time period andbeing characteristic of driver alertness (above the line) andnon-alertness (below the line).

[0169] In reality, this threshold line may be fixed or variable as theresult of variations in one or more parameters, including, inter alia,vehicle speed, elapsed duration of trip, known or earlier determineddriving characteristics of the driver, travel conditions and type ofvehicle.

[0170] A determination of driver alertness or non-alertness may be acumulative determination based on a weighting of the points appearingabove and below the threshold line, once a statistically acceptablesample is achieved (steps 604 and 606, FIG. 6). Alternatively oradditionally, it may be a determination based on the change in theposition of successive points relative to the threshold line andrelative to each other as time passes.

[0171] Based on the determination of driver alertness or non-alertnessmade from time to time, an appropriate alarm indication is provided tothe driver (step 608, FIG. 6), preferably via alarm 136 (FIG. 2).

[0172] It will be appreciated by persons skilled in the art that thepresent invention is not limited by what has been particularly shown anddescribed hereinabove. Rather the scope of the present inventionincludes both combinations and subcombinations of the various featuresdescribed hereinabove as well as variations and modifications whichwould occur to persons skilled in the art upon reading the specificationand which are not in the prior art.

1. A methodology for determining the alertness of a driver of a motorvehicle comprising: sensing at least one first movement characteristicof at least a first part of a motor vehicle; sensing at least one secondmovement characteristic of at least a second part of said motor vehicle;employing at least one time relationship between said at least one firstmovement characteristic and said at least one second movementcharacteristic in order to sense and to distinguish between driverinitiated movements and non-driver initiated movements; and determiningthe alertness of said driver of said motor vehicle based on at least onerelationship between said driver initiated movements and said non-driverinitiated movements.
 2. A methodology according to claim 1 and whereinsaid at least one first movement characteristic comprises a steeringwheel movement characteristic and said at least one second movementcharacteristic comprises a road wheel movement characteristic.
 3. Amethodology according to claim 1 and wherein said at least one firstmovement characteristic and said at least one second movementcharacteristic comprise movement characteristics of first and secondlocations along a steering assembly extending from a steering wheel toat least one road wheel of said motor vehicle.
 4. A methodologyaccording to claim 1 and wherein said at least one first movementcharacteristic comprises a steering assembly movement characteristic andsaid at least one second movement characteristic comprises a vehiclebody movement characteristic.
 5. A methodology according to claim 1 andwherein said at least one first movement characteristic comprises asteering assembly movement characteristic and said at least one secondmovement characteristic comprises a vehicle chassis movementcharacteristic.
 6. A methodology according to claim 3 and wherein saidfirst and second locations are located respectively at or upstream ofand at or downstream of a power steering unit forming part of saidsteering assembly.
 7. A methodology according to claim 6 and whereinsaid first location is at a steering wheel forming part of said steeringassembly.
 8. A methodology according to claim 2 and wherein: said atleast one first movement characteristic is angular displacement of saidsteering wheel; and said at least one second movement characteristic isa steering angle of at least one road wheel.
 9. A methodology accordingto claim 3 and wherein: said at least one first movement characteristicis displacement; and said at least one second movement characteristic isdisplacement.
 10. A methodology according to claim 4 and wherein: saidat least one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 11. A methodology according to claim 5 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 12. A methodology according to claim 6 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is displacement.
 13. Amethodology for determining the alertness of a driver of a motor vehiclecomprising: employing at least one time relationship between at leastone first movement characteristic of at least a first part of a motorvehicle and at least one second movement characteristic of at least asecond part of said motor vehicle in order to sense and to distinguishbetween driver initiated movements and non-driver initiated movements;and determining the alertness of said driver of said motor vehicle basedon at least one relationship between said driver initiated movements andsaid non-driver initiated movements.
 14. A methodology according toclaim 13 and wherein said at least one first movement characteristiccomprises a steering wheel movement characteristic and said at least onesecond movement characteristic comprises a road wheel movementcharacteristic.
 15. A methodology according to claim 13 and wherein saidat least one first movement characteristic and the second movementcharacteristic comprise movement characteristics of first and secondlocations along a steering assembly extending from a steering wheel toat least one road wheel of said motor vehicle.
 16. A methodologyaccording to claim 13 and wherein said at least one first movementcharacteristic comprises a steering assembly movement characteristic andsaid at least one second movement characteristic comprises a vehiclebody movement characteristic.
 17. A methodology according to claim 13and wherein said at least one first movement characteristic comprises asteering assembly movement characteristic and said at least one secondmovement characteristic comprises a vehicle chassis movementcharacteristic.
 18. A methodology according to claim 15 and wherein saidfirst and second locations are located respectively at or upstream ofand at or downstream of a power steering unit forming part of saidsteering assembly.
 19. A methodology according to claim 18 and whereinsaid first location is at a steering wheel forming part of said steeringassembly.
 20. A methodology according to claim 14 and wherein: said atleast one first movement characteristic is angular displacement of saidsteering wheel; and said at least one second movement characteristic isa steering angle of at least one road wheel.
 21. A methodology accordingto claim 15 and wherein: said at least one first movement characteristicis displacement; and said at least one second movement characteristic isdisplacement.
 22. A methodology according to claim 16 and wherein: saidat least one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 23. A methodology according to claim 17 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 24. A methodology according to claim 18 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is displacement.
 25. Amethodology for determining the alertness of a driver of a motor vehiclecomprising: sensing at least one first movement characteristic of atleast a first part of a motor vehicle; sensing at least one secondmovement characteristic of at least a second part of a motor vehicle;and employing said at least one first movement characteristic and saidat least one second movement characteristic in order to determine thealertness of said driver of said motor vehicle.
 26. A methodologyaccording to claim 25 and wherein said at least one first movementcharacteristic comprises a steering wheel movement characteristic andsaid at least one second movement characteristic comprises a road wheelmovement characteristic.
 27. A methodology according to claim 25 andwherein said at least one first movement characteristic and the secondmovement characteristic comprise movement characteristics of first andsecond locations along a steering assembly extending from a steeringwheel to at least one road wheel of said motor vehicle.
 28. Amethodology according to claim 25 and wherein said at least one firstmovement characteristic comprises a steering assembly movementcharacteristic and said at least one second movement characteristiccomprises a vehicle body movement characteristic.
 29. A methodologyaccording to claim 25 and wherein said at least one first movementcharacteristic comprises a steering assembly movement characteristic andsaid at least one second movement characteristic comprises a vehiclechassis movement characteristic.
 30. A methodology according to claim 27and wherein said first and second locations are located respectively ator upstream of and at or downstream of a power steering unit formingpart of said steering assembly.
 31. A methodology according to claim 30and wherein said first location is at a steering wheel forming part ofsaid steering assembly.
 32. A methodology according to claim 26 andwherein: said at least one first movement characteristic is angulardisplacement of said steering wheel; and said at least one secondmovement characteristic is a steering angle of at least one road wheel.33. A methodology according to claim 27 and wherein: said at least onefirst movement characteristic is displacement; and said at least onesecond movement characteristic is displacement.
 34. A methodologyaccording to claim 28 and wherein: said at least one first movementcharacteristic is displacement; and said at least one second movementcharacteristic is acceleration in at least one direction.
 35. Amethodology according to claim 29 and wherein: said at least one firstmovement characteristic is displacement; and said at least one secondmovement characteristic is acceleration in at least one direction.
 36. Amethodology according to claim 30 and wherein: said at least one firstmovement characteristic is displacement; and said at least one secondmovement characteristic is displacement.
 37. A methodology fordetermining the alertness of a driver of a motor vehicle comprising:sensing at least one first movement characteristic of at least a firstpart of a motor vehicle; sensing at least one second movementcharacteristic of at least a second part of said motor vehicle;employing said at least one first movement characteristic and said atleast one second movement characteristic in order to sense driverinitiated movements; and determining the alertness of said driver ofsaid motor vehicle based at least partially on said sensed driverinitiated movements.
 38. A methodology according to claim 37 and whereinsaid at least one first movement characteristic comprises a steeringwheel movement characteristic and said at least one second movementcharacteristic comprises a road wheel movement characteristic.
 39. Amethodology according to claim 37 and wherein said at least one firstmovement characteristic and the second movement characteristic comprisemovement characteristics of first and second locations along a steeringassembly extending from a steering wheel to at least one road wheel ofsaid motor vehicle.
 40. A methodology according to claim 37 and whereinsaid at least one first movement characteristic comprises a steeringassembly movement characteristic and said at least one second movementcharacteristic comprises a vehicle body movement characteristic.
 41. Amethodology according to claim 37 and wherein said at least one firstmovement characteristic comprises a steering assembly movementcharacteristic and said at least one second movement characteristiccomprises a vehicle chassis movement characteristic.
 42. A methodologyaccording to claim 39 and wherein said first and second locations arelocated respectively at or upstream of and at or downstream of a powersteering unit forming part of said steering assembly.
 43. A methodologyaccording to claim 42 and wherein said first location is at a steeringwheel forming part of said steering assembly.
 44. A methodologyaccording to claim 38 and wherein: said at least one first movementcharacteristic is angular displacement of said steering wheel; and saidat least one second movement characteristic is a steering angle of atleast one road wheel.
 45. A methodology according to claim 39 andwherein: said at least one first movement characteristic isdisplacement; and said at least one second movement characteristic isdisplacement.
 46. A methodology according to claim 40 and wherein: saidat least one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 47. A methodology according to claim 41 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 48. A methodology according to claim 42 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is displacement.
 49. Amethodology for determining the alertness of a driver of a motor vehiclecomprising: sensing at least one characteristic of driver initiatedmovements of at least one part of a motor vehicle; sensing at least onecharacteristic of non-driver initiated movements of at least one part ofa motor vehicle; and determining the alertness of said driver of saidmotor vehicle based on at least one relationship between said driverinitiated movements and said non-driver initiated movements.
 50. Amethodology according to claim 49 and wherein said at least onecharacteristic of driver initiated movements is extent.
 51. Amethodology according to claim 49 and wherein said at least onecharacteristics of non-driver initiated movements is extent.
 52. Amethodology according to claim 50 and wherein said at least onecharacteristics of non-driver initiated movements is extent.
 53. Amethodology according to claim 50 and wherein extent of driver initiatedmovements includes at least one of: the integrated magnitude of thedriver initiated movements; the RMS average of the magnitude of thedriver initiated movements; the number of peaks of the driver initiatedmovements per unit time.
 54. A methodology according to claim 51 andwherein extent of non-driver initiated movements includes at least oneof: the integrated magnitude of the non-driver initiated movements; theRMS average of the magnitude of the non-driver initiated movements; thenumber of peaks of the non-driver initiated movements per unit time. 55.A methodology according to claim 49 and wherein said sensing at leastone characteristic of driver initiated movements of at least one part ofa motor vehicle and said sensing at least one characteristic ofnon-driver initiated movements of at least one part of a motor vehiclecomprise sensing at least one first movement characteristic and sensingat least one second movement characteristic of said motor vehicle.
 56. Amethodology according to claim 55 and wherein said at least one firstmovement characteristic comprises a steering wheel movementcharacteristic and said at least one second movement characteristiccomprises a road wheel movement characteristic.
 57. A methodologyaccording to claim 56 and wherein said at least one first movementcharacteristic and the second movement characteristic comprise movementcharacteristics of first and second locations along a steering assemblyextending from a steering wheel to at least one road wheel of said motorvehicle.
 58. A methodology according to claim 56 and wherein said atleast one first movement characteristic comprises a steering assemblymovement characteristic and said at least one second movementcharacteristic comprises a vehicle body movement characteristic.
 59. Amethodology according to claim 56 and wherein said at least one firstmovement characteristic comprises a steering assembly movementcharacteristic and said at least one second movement characteristiccomprises a vehicle chassis movement characteristic.
 60. A methodologyaccording to claim 57 and wherein said first and second locations arelocated respectively at or upstream of and at or downstream of a powersteering unit forming part of said steering assembly.
 61. A methodologyaccording to claim 60 and wherein said first location is at a steeringwheel forming p art of said steering assembly.
 62. A methodologyaccording to claim 60 and wherein: said at least one first movementcharacteristic is angular displacement of said steering wheel; and saidat least one second movement characteristic is a steering angle of atleast one road wheel.
 63. A methodology according to claim 57 andwherein: said at least one first movement characteristic isdisplacement; and said at least one second movement characteristic isdisplacement.
 64. A methodology according to claim 58 and wherein: saidat least one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 65. A methodology according to claim 59 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 66. A methodology according to claim 60 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is displacement.
 67. Amethodology according to claim 1 and wherein said determining alsoemploys the speed of the vehicle.
 68. A methodology according to claim13 and wherein said determining also employs the speed of the vehicle.69. A methodology according to claim 25 and wherein said determiningalso employs the speed of the vehicle.
 70. A methodology according toclaim 37 and wherein said determining also employs the speed of thevehicle.
 71. A system for determining the alertness of a driver of amotor vehicle comprising: a first sensor sensing at least one firstmovement characteristic of at least a first part of a motor vehicle; asecond sensor sensing at least one second movement characteristic of atleast a second part of said motor vehicle; a distinguisher, employing atleast one time relationship between said at least one first movementcharacteristic and said at least one second movement characteristic inorder to sense and to distinguish between driver initiated movements andnon-driver initiated movements; and an alertness determiner, determiningthe alertness of said driver of said motor vehicle based on at least onerelationship between said driver initiated movements and said non-driverinitiated movements.
 72. A system according to claim 71 and wherein saidat least one first movement characteristic comprises a steering wheelmovement characteristic and said at least one second movementcharacteristic comprises a road wheel movement characteristic.
 73. Asystem according to claim 71 and wherein said at least one firstmovement characteristic and said at least one second movementcharacteristic comprise movement characteristics of first and secondlocations along a steering assembly extending from a steering wheel toat least one road wheel of said motor vehicle.
 74. A system according toclaim 71 and wherein said at least one first movement characteristiccomprises a steering assembly movement characteristic and said at leastone second movement characteristic comprises a vehicle body movementcharacteristic.
 75. A system according to claim 71 and wherein said atleast one first movement characteristic comprises a steering assemblymovement characteristic and said at least one second movementcharacteristic comprises a vehicle chassis movement characteristic. 76.A system according to claim 73 and wherein said first and secondlocations are located respectively at or upstream of and at ordownstream of a power steering unit forming part of said steeringassembly.
 77. A system according to claim 76 and wherein said firstlocation is at a steering wheel forming part of said steering assembly.78. A system according to claim 72 and wherein: said at least one firstmovement characteristic is angular displacement of said steering wheel;and said at least one second movement characteristic is a steering angleof at least one road wheel.
 79. A system according to claim 73 andwherein: said at least one first movement characteristic isdisplacement; and said at least one second movement characteristic isdisplacement.
 80. A system according to claim 74 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 81. A system according to claim 75 and wherein: said at leastone first movement characteristic is displacement; and said at least onesecond movement characteristic is acceleration in at least onedirection.
 82. A system according to claim 76 and wherein: said at leastone first movement characteristic is displacement; and said at least onesecond movement characteristic is displacement.
 83. A system fordetermining the alertness of a driver of a motor vehicle comprising: adistinguisher, employing at least one time relationship between at leastone first movement characteristic of at least a first part of a motorvehicle and at least one second movement characteristic of at least asecond part of said motor vehicle in order to sense and to distinguishbetween driver initiated movements and non-driver initiated movements;and an alertness determiner, determining the alertness of said driver ofsaid motor vehicle based on at least one relationship between saiddriver initiated movements and said non-driver initiated movements. 84.A system according to claim 83 and wherein said at least one firstmovement characteristic comprises a steering wheel movementcharacteristic and said at least one second movement characteristiccomprises a road wheel movement characteristic.
 85. A system accordingto claim 83 and wherein said at least one first movement characteristicand the second movement characteristic comprise movement characteristicsof first and second locations along a steering assembly extending from asteering wheel to at least one road wheel of said motor vehicle.
 86. Asystem according to claim 83 and wherein said at least one firstmovement characteristic comprises a steering assembly movementcharacteristic and said at least one second movement characteristiccomprises a vehicle body movement characteristic.
 87. A system accordingto claim 83 and wherein said at least one first movement characteristiccomprises a steering assembly movement characteristic and said at leastone second movement characteristic comprises a vehicle chassis movementcharacteristic.
 88. A system according to claim 85 and wherein saidfirst and second locations are located respectively at or upstream ofand at or downstream of a power steering unit forming part of saidsteering assembly.
 89. A system according to claim 88 and wherein saidfirst location is at a steering wheel forming part of said steeringassembly.
 90. A system according to claim 84 and wherein: said at leastone first movement characteristic is angular displacement of saidsteering wheel; and said at least one second movement characteristic isa steering angle of at least one road wheel.
 91. A system according toclaim 85 and wherein: said at least one first movement characteristic isdisplacement; and said at least one second movement characteristic isdisplacement.
 92. A system according to claim 86 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 93. A system according to claim 87 and wherein: said at leastone first movement characteristic is displacement; and said at least onesecond movement characteristic is acceleration in at least onedirection.
 94. A system according to claim 88 and wherein: said at leastone first movement characteristic is displacement; and said at least onesecond movement characteristic is displacement.
 95. A system fordetermining the alertness of a driver of a motor vehicle comprising: afirst sensor, sensing at least one first movement characteristic of atleast a first part of a motor vehicle; a second sensor, sensing at leastone second movement characteristic of at least a second part of a motorvehicle; and a distinguisher, employing said at least one first movementcharacteristic and said at least one second movement characteristic inorder to determine the alertness of said driver of said motor vehicle.96. A system according to claim 95 and wherein said at least one firstmovement characteristic comprises a steering wheel movementcharacteristic and said at least one second movement characteristiccomprises a road wheel movement characteristic.
 97. A system accordingto claim 95 and wherein said at least one first movement characteristicand the second movement characteristic comprise movement characteristicsof first and second locations along a steering assembly extending from asteering wheel to at least one road wheel of said motor vehicle.
 98. Asystem according to claim 95 and wherein said at least one firstmovement characteristic comprises a steering assembly movementcharacteristic and said at least one second movement characteristiccomprises a vehicle body movement characteristic.
 99. A system accordingto claim 95 and wherein said at least one first movement characteristiccomprises a steering assembly movement characteristic and said at leastone second movement characteristic comprises a vehicle chassis movementcharacteristic.
 100. A system according to claim 97 and wherein saidfirst and second locations are located respectively at or upstream ofand at or downstream of a power steering unit forming part of saidsteering assembly.
 101. A system according to claim 100 and wherein saidfirst location is at a steering wheel forming part of said steeringassembly.
 102. A system according to claim 96 and wherein: said at leastone first movement characteristic is angular displacement of saidsteering wheel; and said at least one second movement characteristic isa steering angle of at least one road wheel.
 103. A system according toclaim 97 and wherein: said at least one first movement characteristic isdisplacement; and said at least one second movement characteristic isdisplacement.
 104. A system according to claim 98 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 105. A system according to claim 99 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 106. A system according to claim 100 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is displacement.
 107. A systemfor determining the alertness of a driver of a motor vehicle comprising:a first sensor, sensing at least one first movement characteristic of atleast a first part of a motor vehicle; a second sensor, sensing at leastone second movement characteristic of at least a second part of saidmotor vehicle; a distinguisher, employing said at least one firstmovement characteristic and said at least one second movementcharacteristic in order to sense driver initiated movements; and analertness determiner, determining the alertness of said driver of saidmotor vehicle based at least partially on said sensed driver initiatedmovements.
 108. A system according to claim 107 and wherein said atleast one first movement characteristic comprises a steering wheelmovement characteristic and said at least one second movementcharacteristic comprises a road wheel movement characteristic.
 109. Asystem according to claim 107 and wherein said at least one firstmovement characteristic and the second movement characteristic comprisemovement characteristics of first and second locations along a steeringassembly extending from a steering wheel to at least one road wheel ofsaid motor vehicle.
 110. A system according to claim 107 and whereinsaid at least one first movement characteristic comprises a steeringassembly movement characteristic and said at least one second movementcharacteristic comprises a vehicle body movement characteristic.
 111. Asystem according to claim 107 and wherein said at least one firstmovement characteristic comprises a steering assembly movementcharacteristic and said at least one second movement characteristiccomprises a vehicle chassis movement characteristic.
 112. A systemaccording to claim 109 and wherein said first and second locations arelocated respectively at or upstream of and at or downstream of a powersteering unit forming part of said steering assembly.
 113. A systemaccording to claim 112 and wherein said first location is at a steeringwheel forming part of said steering assembly.
 114. A system according toclaim 108 and wherein: said at least one first movement characteristicis angular displacement of said steering wheel; and said at least onesecond movement characteristic is a steering angle of at least one roadwheel.
 115. A system according to claim 109 and wherein: said at leastone first movement characteristic is displacement; and said at least onesecond movement characteristic is displacement.
 116. A system accordingto claim 1 10 and wherein: said at least one first movementcharacteristic is displacement; and said at least one second movementcharacteristic is acceleration in at least one direction.
 117. A systemaccording to claim 11 1 and wherein: said at least one first movementcharacteristic is displacement; and said at least one second movementcharacteristic is acceleration in at least one direction.
 118. A systemaccording to claim 112 and wherein: said at least one first movementcharacteristic is displacement; and said at least one second movementcharacteristic is displacement.
 119. A system for determining thealertness of a driver of a motor vehicle comprising: a driver initiatedmovement sensor, sensing at least one characteristic of driver initiatedmovements of at least one part of a motor vehicle; a non-driverinitiated movement sensor, sensing at least one characteristic ofnon-driver initiated movements of at least one part of a motor vehicle;and a determiner, determining the alertness of said driver of said motorvehicle based on at least one relationship between said driver initiatedmovements and said non-driver initiated movements.
 120. A systemaccording to claim 119 and wherein said at least one characteristic ofdriver initiated movements is extent.
 121. A system according to claim119 and wherein said at least one characteristics of non-driverinitiated movements is extent.
 122. A system according to claim 120 andwherein said at least one characteristics of non-driver initiatedmovements is extent.
 123. A system according to claim 120 and whereinextent of driver initiated movements includes at least one of: theintegrated magnitude of the driver initiated movements; the RMS averageof the magnitude of the driver initiated movements; the number of peaksof the driver initiated movements per unit time.
 124. A system accordingto claim 121 and wherein extent of non-driver initiated movementsincludes at least one of: the integrated magnitude of the non-driverinitiated movements; the RMS average of the magnitude of the non-driverinitiated movements; the number of peaks of the non-driver initiatedmovements per unit time.
 125. A system according to claim 119 andwherein said driver initiated movement sensor sensing at least onecharacteristic of driver initiated movements of at least one part of amotor vehicle and said non-driver initiated movement sensor sensing atleast one characteristic of non-driver initiated movements of at leastone part of a motor vehicle comprise a first sensor, sensing at leastone first movement characteristic and a second sensor sensing at leastone second movement characteristic of said motor vehicle.
 126. A systemaccording to claim 125 and wherein said at least one first movementcharacteristic comprises a steering wheel movement characteristic andsaid at least one second movement characteristic comprises a road wheelmovement characteristic.
 127. A system according to claim 126 andwherein said at least one first movement characteristic and the secondmovement characteristic comprise movement characteristics of first andsecond locations along a steering assembly extending from a steeringwheel to at least one road wheel of said motor vehicle.
 128. A systemaccording to claim 126 and wherein said at least one first movementcharacteristic comprises a steering assembly movement characteristic andsaid at least one second movement characteristic comprises a vehiclebody movement characteristic.
 129. A system according to claim 126 andwherein said at least one first movement characteristic comprises asteering assembly movement characteristic and said at least one secondmovement characteristic comprises a vehicle chassis movementcharacteristic.
 130. A system according to claim 127 and wherein saidfirst and second locations are located respectively at or upstream ofand at or downstream of a power steering unit forming part of saidsteering assembly.
 131. A system according to claim 130 and wherein saidfirst location is at a steering wheel forming part of said steeringassembly.
 132. A system according to claim 130 and wherein: said atleast one first movement characteristic is angular displacement of saidsteering wheel; and said at least one second movement characteristic isa steering angle of at least one road wheel.
 133. A system according toclaim 127 and wherein: said at least one first movement characteristicis displacement; and said at least one second movement characteristic isdisplacement.
 134. A system according to claim 128 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 135. A system according to claim 129 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is acceleration in at least onedirection.
 136. A system according to claim 130 and wherein: said atleast one first movement characteristic is displacement; and said atleast one second movement characteristic is displacement.
 137. A systemaccording to claim 78 and wherein said determining also employs thespeed of the vehicle.
 138. A system according to claim 83 and whereinsaid determining also employs the speed of the vehicle.
 139. A systemaccording to claim 95 and wherein said determining also employs thespeed of the vehicle.
 140. A system according to claim 107 and whereinsaid determining also employs the speed of the vehicle.
 141. A systemaccording to claim 71 and also comprising a driver alertness alarm,responsive to an alarm from said driver alertness determiner forproviding an alarm to a driver deemed not to be sufficiently alert. 142.A system according to claim 83 and also comprising a driver alertnessalarm, responsive to an alarm from said driver alertness determiner forproviding an alarm to a driver deemed not to be sufficiently alert. 143.A system according to claim 95 and also comprising a driver alertnessalarm, responsive to an alarm from said driver alertness determiner forproviding an alarm to a driver deemed not to be sufficiently alert. 144.A system according to claim 107 and also comprising a driver alertnessalarm, responsive to an alarm from said driver alertness determiner forproviding an alarm to a driver deemed not to be sufficiently alert. 145.A system according to claim 119 and also comprising a driver alertnessalarm, responsive to an alarm from said driver alertness determiner forproviding an alarm to a driver deemed not to be sufficiently alert.